Speed-change mechanism



R. E. WINTERS.

SPE-ED CHANGE '.MECHANISM. APPucATloN FILED mm1?, 1920.

Patented Feb. 28, 1922.

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r R. E. WINTERS. SPEED CHANGE MKECHANISM. APPLlcATloN .FILED MAn. l-. 1920. 1 ,407,716. Patented Feb. 28, 1922.

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' UNITED STATES PATENT oFFlcr..

ROBERT E. WINT'ERS. or ooRAoroLrs, PENNSYLVANIA, AssreNoR or ONE-HALF To y ANTHONY E. DEAN, FPITTSBURGH, PENNSYLVANIA.

SEEB-CH.ANGEl MECHAN ISM.

rationale.

Specication ofilietters'p'atent. jffvgrfgvned Feb9 28, 1922,

Application led March 17l1920. Serial No. 366,490.

To c?! whom t 'may concern;

lie it known that l.. onmrr lll. l'iNi'rnRs,

a citizen of the UnitedStates, and resident of Coraopolis, in the county of Allegheny and State of Pennsylvanimh ave invented a new and useful Vimprovement in Speed- Change Mechanism, of which the following is a specification. v

This invention relates to a speed change mechanism and constitutes an improvement over the device of Patent No. 1,352,716, dated September 14, 41920.

The object of the invention is to provide mechanism for use inmotor driven vehicles, or stationary machinery, by means of which gear shifting arrangements are rendered unnecessary. K f f n .a further object .of the invention is to proifide meansl which operate smoothly in changing speeds, which areso compactly arranged as to occupy a relatively small space,

and which are strong and simple inconstruction. n

lnthe accompanying drawings'lig; 1 is a rear elevation of the device with a portion of the housing removed; F ig. 2 is a central vertical section throughl the device; Fig. 3 is a section on the line 3 3, Fig. 2; Fig. 4 is a front elevation of the deviceglfig. 5 is an enlarged detail of a portion `of the controlling means of` the device; Fig., 6 isa view thereof partly in elevation and partlyin section; Fig. 7 is a detail view of the brake mechanism by means of which the change of speed is controlled; and Fig. 8 is a fragmentary sectional detail of a portion of the brake operating means.A

The device comprises a main housing 1 and an auxiliary housing-2, within both of which the main operating parts of the mechanism are contained. v

lVithin the housing 1 is the power tyransmitting wheel 3 secured to the power operated shaft l of a motor. This portion of the device corresponds in .general to that of the prior application noted above; and .has for the 'transmission of powerto a pitman 5, the pin 6, which is adjustable along thev diameter ofthe wheel 3 in a slot 8 therein, and which engages in a slot 7 in the pitman. f

For adjusting the position of the pin, a Worm shaft 9 passes-through theV thickest portion of the pin 6 and is threadedto itin-- in the teriorally. The shaft 9 is rotatably mounted Wheel 3 so lthatits rotation causes a rectilinear movement of the pin. On one extremity of the shaft .9 is a pinionrlOmeshing with a pairof-circular racks 11 and12 on rings 13 and le engaged frictionallyon thewheel plurality of toothed spacers 10a'l are .inserted around the periphery of wheel 3 between rings 13 and 14. 4Bearing agi-inist rings 13 and 14 respectively are pressure arms 15 and 16,A which are acted upon by cam rods 15A and 16a. The cam rods le and 1G are operated bylmeans of rock levers 17 and 17h `mounted on a` shaft 17c i operated bylever 17. The pressure arms 15 and 1G bear on theperipheries of rings 13 and 141 to serve as'friction brakes for stoppingk or retarding rotation of either ring with the wheel In such case the station-A.

ary or retarded ring, slipping on thel periphery of the wheel, acts as a rackon'the pinion 10 as the latter moves with` the wheel, rotating the worm. shaft 9.

The rotation of-worm shaft 9 moves the pin G either away from or toward the center of slots 7 and It will be understood that if the pin is in the center ofthe slots the device is in neutral position and no motion will be imparted tothe pitman 5. Also, the greater the distance from the center to which the pin is moved, the greater will be' the length of stroke of the pitman and the greater the speed it can impart,

Novel features of the present invention reside in the means for converting the reciprocatory movement of pitman 5 into Inovement of rotation of a power shaft 18.

. Forthispurposc a pair of worm racks 19 and 20 are secured to the pitman 5, and are slidable together kwith the pitman on stationary shafts 21 mountedin the housing 2. These wormracks 19 and 20 meshwith a worin 'gear 22 which is on the power shaft 18, the power shaft being journaled iat 23 l in the housing 2. As the shafty 18 is to be rotated continuously in one directioinlit is evident that the worm racks 19 and 2O must act alternately upon the wormgear 22 in order to secure suchv continuous rotation.

This effect is secured partially by the variations in pressure exerted on the racks by the worms at the limit of the strokes of the pitman, and partially by certain governing means arranged yto kcause rotation of one rack while holding the other against rotation.

Such governing means comprise a shaft 24 secured to the pitman to move therewith and passing through the Wall of housing 2. On

shaft 24 are a pair of spur gears 25'and 26." The gear 25 meshes with a pinion 27 on rack Y 19, while gear 26 meshes With a pinionk 28' Von rack 20. Secured to gears 25fand 26 respectively, are a pair of bevel ring gears29` and 30,'which are oppositely faced and which bothmesh with bevel pinioiis 31. `The bevel ring gears 'largement 24a of the shaft 24. v In'this entained vin position in -ing engagement With the ring gears 29 and 30,V and by the surrounding portion of thel "View, during which the movement pose the rotation ot Worin gear 22.

lwill cause the teeth ot rack 20' to exert "against those ot worm gear 22 apressure held against rotation. creased bythe `29 is :tree

29 and 30 are free upon an enlarged portion 24ZL are cups 31 in .which the bevel pinionsBl lie. The pinions are mainthe cups by their nieshfraine 2.

V In operation of the device, weinay assume that the pitman 5 has just reached the 'extreme limit of its stroketroni right to lett in Fig. 1; the upper rack 19 during this stroke acting upon Worm gear 22 to cause its rotation. As the pitnian begins its ure-` turn lstroke there Will be an instant oi time,

negligible from ay disadvantageous point ot n ot loiver 'rack 2O from left to right will tend te opgreatly in excess oi, that exerted by raclr19. A pinor lug 32 engages in a` spiral groove -in a sleeve 38 rigidly secured to ther sh a tt This pin is held in a bracket 34, which is -secured to housing 2 and maintains the lug 32 in position to engage in the spiral grooif'e in the sleeve on shaft 24.' rthis lng 32 is adjustable in the bracket 34 by means ott' :set screw 36 so thatit maybe set'in proper position before use ot the device.

As the pitman 5 reciprocates, moving from leiit to right, this engagement ,causes rotation ot shaft 24. carrying the spin" gears 25 and 26. Since the pressure oit the teeth t' rack 2O upon those ot WormV 22 isA great, there a tendency for the rack 26, together With lspur gears 26 and 2S, to be rEhis tendency is inp actiono't the bevel ring vgears 29"and 30 and the bevel pinions 31. ln the instance given, as there is a tendency .tor the spur gear 26 to be held against rotation ring gear 36 is also held. but 'the ring gear portionr24a. The bevel/pinions 31 also rotate as theytravel with shaft '24 on the stationary ring gear 30, and bytheir action increase the speed of rotation of rin-g gear 29 and. consequently that of spur gear 25 to Which it is secured.

It will be seen that when once this action has been started, it will continue so long as gear 22.

This

to rotate on the enlarged shaft lbe provided.'Vv VSuch means comprise a vane the pitman moves in' the saine cirection,

Y the spur gears 25 vloeingrotated at a high gears 26and 20, are held with such speed that it leads the rotation ofV Worm gear 22, and its teeth exert no pres-` sure on those ofthe VWorm (rear tending to oppose its rotation in vthe proper direction.` During the return movement ofthe pitinan' Vtrom right to left, the effect .is exactly opposite. In this Ycase the rack 19 is held Aby the pressure of its teeth upon those ot Worm gear 22, and the rack 20 is rotated the spur gear 26 and pinion 28 on the to cause rotation oie.V the rack 20 at such speed as to lead the` rotation of Worm It is to be understood that the momentum of pitma'n movement changes Vthe action oi' lthe yWorm rackson the Worin hgear Within 2O is held against rotation,

such an immeasurably short instant or' time that the actionV proceeds Without 4any such slackening in the speed at which the power shaft is rotated, as cannot be corrected by the inertia of a-lyivheel or olf a vehicle in which the device is employed. i The reversingmeans for the devicelconi prise a reversing lever 37, which has a Vhub portion 38 .screw threaded in the housing 2 and arranged to cooperate ivithshoulder 39 onrack 19. The Vreversing leverBZ iiiay be operated by any convenient meanslsucli as the operating lever 40.

lV-hen lever-37 isthrown, it moves in Wardlyloy means ot its screiv` threaded engagement with housing 2 and coming into contact With shoulder 39 on the worm serves to so modify the pressure exerted by its teeth on those of Worin gear 22 as to cause l. o l' a reversal oitlie action or the racks 19 and 20, diie to thechangein tlieir'action inter mediate the limit of. the pitman stroke. This obviously causesa reversalv in the direction of `rotation ot vv'ormV gear 22 and power shaft'18.

ifflutomatie'l speed regulating means yas il* lustrated in the drawings, may, ir' desired,

41 Aorra collar 42, which' is both rotatably and slldably moiintedfontlie `engine shaft 4.

In a pcripheralseat 422in collar 42 lits a hook member 43 on a 'lever arm 44. The

`lever arm 44 is 4it'ulcrumed in abracket 45 on the housing 1A and issecured at its eX- -treniity to rockflever 17 .Y 1 A compression spring 44L bears against the lever arm 44 and' tends to normally maintain collar 42' l n said vpower shaft -meshing with? sai'dlracks,

"in inward position.

The vane 41 thus acts as a governing device, since when the engine shaft exceeds acertain speed, it will tend to creep outf wardly on the shaft against the resistance of spring 44 and 'will `act through `rock lever 17 and the one acted upon and by means of rack 9 and tend to cause movement of pin Vo away from the 'center of'slots 7 and 8.

This action will obviously lengthen the stroke of pitman and' increase the speed at which the power shaft 18 is driven in correspondence with the` increase in engine speed.

i lessening in engine speed will act conversely, the vane creeping inwardly under the force exerted by spring 44a and causing pressure arm 15 to bear upon brake band 13 to rotate the worm shaft 9 in the opposite direction and move pin 6 toward the centers of slots and 8. This action will obviously shorten the stroke of pitman 5, and thus decrease-the speed at which power shaft 18 is driven. If the device is applied to an automobile, and the engine speed slackens because of an upgrade, the pin v6 will be moved toward the center of slots 7 and 8, increasing the power as well as decreasing the speed of rotation of power shaft 18.

It is to be understood that this arrangement is optional only, and that under certain circumstances, it may be preferable to maintain the speed regulating means under the direct control of the operator. In such case the controlling lever may have a connection with a spring held pedal of ordinary design, or may be extended into a hand operable lever.V VEither of these arrangements may be made without dispensing with the automatic governing vane.

rlhe device as a whole is strong and compact; and obviates entirely the necessity for gear shifting arrangements. Not only does it provide a definite neutral position, but also provides a smooth progression in driving speed from minimum Vto maximum.

What 1 claim is: Y

1. ln speed change mechanism a pitman, means for reciprocating said pitman racks on said pitman, a power shaft, a gear on said power shaft meshing with said racks, a govf erning shaft arrangedto be rotated by reciprocation of said pitman, gears on said racks, gears on saidgoverning shaft meshing with each of said rack gears, and means on said shaft arranged to rotate said gears alternately during alternate strokes of the pitman.

2. ln speed change mechanism a pitman,

n pressure arms .15 and 16 upon" the brake bands.` The arrangement is such Y' that in this event the brake band 14 will be governing n l n rotation of the other thereof at an increased meshing with said said pitman,

means for reciprocating s'ayidpitman,l racks on saidl pitman, a power shaft, a Gear on 'gears 'on saidracks, and gears actuated by pitman for rotating said during alternate," pitman `fsa-id power shaft meshing with saidjracks,

gears onf said racks, governing gears actu- 12 and pinion 10, will rotate the worm shaftated' by movement o'f'saidpitman antl'mesh- 'ing with eachof Said rack gears, and means arranged to" falternatelyjhold each of said gears E stationary ,""whilefv causing rate of speed.

4. In speed change mechanism the combination of a pitman, a driven shaft,-a driv- `ng wheel connected therewith, means adjustable in said driving wheel for varying the length of stroke of said pitman, racks on said pitman, a power shaft, a gear on said power shaft meshing with said racks, gears on said racks, and gears actuated by movement of said pitman for rotating said racks alternately during alternate pitman strokes.

5. In speed change mechanism the combination of a pitman, a driven shaft, a driving wheel connected therewith, a pin adjustable in said driving wheel for varying the length of stroke ofV said pitman, racks on said-pitman, a power shaft, a gear on said power shaft meshing with said racks, gears on said racks, gears actuated by movement of said pitman for rotating said racks alternatelyV during alternate pitman strokes; a governing vane on said driven shaft, and connection between said governing vane and said adjustable pin for automatically adjusting the position of the pin in the driving wheel.

6. In speed change mechanism a pitman, means for reciprocating said pitman, racks on said pitman, a power shaft, a gear on said power shaft meshing with said racks, means arranged to alternately rotate one of said racksk while holding the other thereof during alternate strokes of the pitman, and operable means on said pitman arranged to contact one of said racks for reversing the operationV of both thereof. 1

7. In speed change mechanism a pitman, means for reciprocating said pitman, a power shaft, a gear on said power shaft racks, a governing shaft arranged to be rotated by reciprocation of gears on said racks, gears on said governing shaft meshing with each of said rack ranged to rotate said gears alternately during alternate strokes of the pitman, a lever member having an extending portion argears, means on said shaft ar-l ranged to Contact one of saidv racks for revyersing theoperation of both thereof, and means for operating said lever member.

8. ln speed change mechanism a pitman, means for reciprocating said pitman, racks on sad pitmdn, a power shaft, a gear on 'said' power shaft meshing with said racks,

means actuated by movement of the pitmztnv for alternately rotating one of said racks while holding the other thereof during alternate strokes of the pit-man7 a lever member having* an extending'portion arranggged-` to Contact oneof said racks for reversing the y operation ofV both thereof, and means for operating said lever member.

9. In speed ohangemeohanism e pitman, `means for'reclproeating said pltman, reeks .onsaid pitman, ,a power shaft, a gear on said powerfshaftmeshing with said racks, means aotnated'hy movement of the pltman for alternately rotating one of said racks rwhile holding the other thereof during elternate strokes of the ptman, it lever memberhaving a huh portion screw threaded in said pitman, and means for rotatin said lever member for causing movement t ereol to Contact one of said racks forl reversing the operation of Vboth thereof. l,

` In witness whereof, I hereunto setfmy hand 1 y ROBERT E. WINTERS. Witnesses Y i .e

' GRETTA W. 'Ansr l1N,

ANNA CURREN. 

